How Accurate Is Your Sleep Tracker?

By Chris Hutton

Who doesn’t want to know more about their #sleep patterns? With the variety of sleep trackers available, many companies are vying for your attention and your money, Many of these bands promise you more energy, better weight loss, and deeper sleep. Fitness tracker company Basis promises users that wearing their band will help them “Catch every Z.” Withings tells users that its Aura clock will give users “their best sleep.”

But how accurate are these promises?

A recent study from the Consumer electronics Association revealed that 51 percent of #sleep tech users have reported that the simple act of using a sleep tracker improved their sleep quality exponentially. 49 percent of members surveyed also reported that the tracker made them feel healthier.

While this may sound positive, users should note that this reported benefit may be nothing more than the placebo effect caused by the presence of the sensor. In fact, there’s a specific placebo known as the “Hawthorne effect” for when the mere fact of being observed causes a change in behavior. It was discovered by Henry Landsberger during a series of human experiments in a factory in Illinois called Hawthorne Works. The factory had spent eight years investigating how light levels affect work productivity, but Landsberger came to believe that it was his very presence in the building that seemed to have an effect on the worker’s productivity levels, rather than the increased lighting. Humans will change a significant part of their behavior if they are willingly being observed, Landsberger concluded.

Gari Clifford, a professor of biomedical engineeering at Emory University, says that this data isn’t reliable. “Most companies don’t publish analyses in peer reviewed journals so you can’t trust them to reflect accurate sleep,” he said. And there are very few objective studies done on Sleep trackers.

This is why Clifford warns against using Sleep Trackers to diagnose a sleep disorder; they’re not as reliable as professional medical trackers due to a number of inconsistencies of sleep data, including the constantly shifting size of sleep cycles, the relative inability to get a “perfect sleep”, and the relationship between yesterday’s sleep cycle and today’s.

That isn’t to say that sleep trackers aren’t helpful for the every day user. Clifford noted that the very presence of a sleep tracker can cause you to care more about your health. But it can also worsen your insomnia if you’re prone to worry or overthink things.